Audio CD lags systematically with MPlayer?

violagirl23 · 09-09-2007, 09:47 PM

I have an old computer from '99, so when I started MPlayer and my audio CD kept lagging, I assumed it didn't have enough memory. But I closed X and everything except MPlayer, and it did the same thing. It lags every one or two seconds, exactly on the *.6 second mark. This is very deliberate. For example, the second track on the CD lags at 0.6 s, 1.6 s, 2.6 s, 4.6s, 6,6s, 7.6s, and so on. What could be causing this? I have played mp3s with MPlayer and they have run flawlessly.
If some background would help, I run Gentoo Linux.
Also, if this would affect it, this is information about my personal MPlayer (what it says while playing the CD):

MPlayer dev-SVN-rUNKNOWN-4.1.1 (C) 2000-2007 MPlayer Team
CPU: Intel Celeron Covington/Pentium II Deschutes,Tonga/Pentium II Xeon (Family: 6, Model: 5, Stepping: 2)
MMX supported but disabled
CPUflags: MMX: 0 MMX2: 0 3DNow: 0 3DNow2: 0 SSE: 0 SSE2: 0
Compiled for x86 CPU with extensions:

Playing cdda://1.
Found audio CD with 12 tracks.

Track 1
rawaudio file format detected.
==========================================================================
Opening audio decoder: [pcm] Uncompressed PCM audio decoder
AUDIO: 44100 Hz, 2 ch, s16le, 1411.2 kbit/100.00% (ratio: 176400->176400)
Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)
==========================================================================
AO: [alsa] 44100Hz 2ch s16le (2 bytes per sample)
Video: no video
Starting playback...

Does anyone have any idea what could be causing this? The lag is just so deliberate that it is making me so very curious!

Electro · 09-09-2007, 10:32 PM

CD-ROM drives from that time may not handle DAE (Digital Audio Extraction) well or not at all. On some setups ALSA has higher latency, so try using OSS as the audio output device.

Post the output of /sbin/hdparm -v of the optical drive. Also post the output of cat /proc/cpuinfo.

You should re-install mplayer with at least mmx support.

violagirl23 · 09-11-2007, 02:32 PM

MPlayer has been recompiled with MMX support, and still the problem persists. Here is the ouput of cat /proc/cpuinfo:

Quote:

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 5
model name : Pentium II (Deschutes)
stepping : 2
cpu MHz : 398.294
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr
bogomips : 796.97
clflush size : 32

And here is the output of /sbin/hdparm -v:

Quote:

/sbin/hdparm -v /dev/cdrw1

/dev/cdrw1:
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 0 (off)
readahead = 256 (on)
HDIO_GETGEO failed: Inappropriate ioctl for device

I'll look into OSS but whether that is the problem or not... I have no idea. Isn't it deprecated, though?

Electro · 09-11-2007, 04:38 PM

Yes, OSS modules are being deprecated. In some ALSA modules (drivers), the ALSA layer has a little higher latency than its OSS layer. The OSS layer is more direct, so it should have low latency.

If you re-compile mplayer to include mmx and custom-cfags in the USE options, it should be faster. I suggest use -Os and -mtune pentium2 as the cflag.